U.S. patent number 10,219,200 [Application Number 15/090,592] was granted by the patent office on 2019-02-26 for apparatus and method for link setup in wireless communication system.
This patent grant is currently assigned to Samsung Electronics Co., Ltd.. The grantee listed for this patent is Samsung Electronics Co., Ltd.. Invention is credited to Doyoung Jung, Young Myoung Kang, Changyeul Kwon, Myounghwan Lee, Sungrok Yoon.
![](/patent/grant/10219200/US10219200-20190226-D00000.png)
![](/patent/grant/10219200/US10219200-20190226-D00001.png)
![](/patent/grant/10219200/US10219200-20190226-D00002.png)
![](/patent/grant/10219200/US10219200-20190226-D00003.png)
![](/patent/grant/10219200/US10219200-20190226-D00004.png)
![](/patent/grant/10219200/US10219200-20190226-D00005.png)
![](/patent/grant/10219200/US10219200-20190226-D00006.png)
![](/patent/grant/10219200/US10219200-20190226-D00007.png)
![](/patent/grant/10219200/US10219200-20190226-D00008.png)
![](/patent/grant/10219200/US10219200-20190226-D00009.png)
![](/patent/grant/10219200/US10219200-20190226-D00010.png)
View All Diagrams
United States Patent |
10,219,200 |
Yoon , et al. |
February 26, 2019 |
Apparatus and method for link setup in wireless communication
system
Abstract
The present disclosure relates to a communication method and
system for converging a 5th-Generation (5G) communication system
for supporting higher data rates beyond a 4th-Generation (4G)
system with a technology for Internet of Things (IoT). The present
disclosure may be applied to intelligent services based on the 5G
communication technology and the IoT-related technology, such as
smart home, smart building, smart city, smart car, connected car,
health care, digital education, smart retail, security and safety
services. Link setup using different Radio Access Technologies
(RATs) in a wireless communication system is provided. A method for
operating a device supporting a first RAT and a second RAT includes
sending information notifying a discovery interval start time for
the second RAT, using the first RAT, and sending discovery signals
during the discovery interval using the second RAT.
Inventors: |
Yoon; Sungrok (Seoul,
KR), Kang; Young Myoung (Gyeonggi-do, KR),
Kwon; Changyeul (Gyeonggi-do, KR), Lee;
Myounghwan (Gyeonggi-do, KR), Jung; Doyoung
(Gyeonggi-do, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd. |
Gyeonggi-do |
N/A |
KR |
|
|
Assignee: |
Samsung Electronics Co., Ltd.
(Suwon-si, KR)
|
Family
ID: |
57006144 |
Appl.
No.: |
15/090,592 |
Filed: |
April 4, 2016 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20160295502 A1 |
Oct 6, 2016 |
|
Foreign Application Priority Data
|
|
|
|
|
Apr 2, 2015 [KR] |
|
|
10-2015-0046905 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W
48/16 (20130101); H04W 52/0216 (20130101); H04W
52/0229 (20130101); Y02D 70/166 (20180101); Y02D
70/144 (20180101); Y02D 70/1262 (20180101); Y02D
30/70 (20200801); Y02D 70/21 (20180101); Y02D
70/142 (20180101) |
Current International
Class: |
H04W
4/00 (20180101); H04W 48/16 (20090101); H04W
52/02 (20090101) |
Field of
Search: |
;455/434,435.1,436,525 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
WO 2013/090751 |
|
Jun 2013 |
|
WO |
|
2013149189 |
|
Oct 2013 |
|
WO |
|
2013172755 |
|
Nov 2013 |
|
WO |
|
WO 2014/021998 |
|
Feb 2014 |
|
WO |
|
WO 2014/047125 |
|
Mar 2014 |
|
WO |
|
2014124237 |
|
Aug 2014 |
|
WO |
|
WO 2014/160543 |
|
Oct 2014 |
|
WO |
|
2015006637 |
|
Jan 2015 |
|
WO |
|
Other References
IEEE Standard for Information Technology; Part 11: Wireless LAN
Medium Access Control (MAC) and Physical Layer (PHY)
Specifications; Amend. 3; 2012; 628 pages. cited by applicant .
International Search Report dated Jul. 13, 2016 in connection with
International Patent Application No. PCT/KR2016/003233. cited by
applicant .
Written Opinion of the International Searching Authority dated Jul.
13, 2016 in connection with International Patent Application No.
PCT/KR2016/003233. cited by applicant .
Partial European Search Report regarding Application No.
16773424.3, dated Mar. 8, 2018, 17 pages. cited by applicant .
Extended European Search Report regarding Application No.
16773424.3, dated May 25, 2018, 19 pages. cited by
applicant.
|
Primary Examiner: Milord; Marceau
Claims
What is claimed is:
1. A method for operating a device supporting a first radio access
technology (RAT) and a second RAT, comprising: transmitting, by
using the first RAT, to a plurality of other devices, a message to
identify a start time of a discovery interval for the second RAT,
and to notify a band switching; and transmitting, by using the
second RAT, to the plurality of other devices, discovery signals
through a plurality of beams during the discovery interval, wherein
the first RAT provides a coverage that is wider than the second
RAT.
2. The method of claim 1, further comprising: adjusting a beamwidth
of the discovery signals based on at least one of signal strength
of the first RAT and a service attribute using the second RAT.
3. The method of claim 1, further comprising: transmitting
information regarding at least one of a discovery signal beamwidth
and a number of beam sectors of the discovery signal, by using the
first RAT.
4. The method of claim 1, further comprising: receiving an
acknowledgement (ACK) responding to the message; and if receiving
the ACK from all of candidate devices, suspending transmitting of
the message.
5. The method of claim 1, further comprising: allocating slots of
the discovery interval to the plurality of other devices; detecting
a discovery signal transmit (TX)-beamformed by each of the
plurality of other devices in the slots; and transmitting feedback
notifying a discovery signal detection result, to each of the
plurality of other devices.
6. The method of claim 1, further comprising: transmitting a signal
notifying a list of at least one other device for data sharing.
7. The method of claim 1, wherein the message comprises information
which represents a remaining time period until the band switching
is performed.
8. A device for supporting a first radio access technology (RAT)
and a second RAT, comprising: a first transceiver configured to
transmit, by using the first RAT, to a plurality of other devices,
a message to identify a start time of a discovery interval for the
second RAT, and to notify a band switching; and a second
transceiver configured to transmit, by using the second RAT, to the
plurality of other device, discovery signals through a plurality of
beams during the discovery interval, wherein the first RAT provides
a coverage that is wider than the second RAT.
9. The device of claim 8, further comprising: at least one
processor configured to adjust a beamwidth of the discovery signals
based on at least one of signal strength of the first RAT and a
service attribute using the second RAT.
10. The device of claim 8, wherein the first transceiver is further
configured to transmit information regarding at least one of a
discovery signal beamwidth and a number of beam sectors of the
discovery signal, by using the first RAT.
11. The device of claim 8, wherein the first transceiver is further
configured to receive an acknowledgement (ACK) responding to the
message, and further comprising: at least one processor configured
to, if receiving the ACK from all of candidate devices, suspend
transmitting of the message.
12. The device of claim 8, further comprising: at least one
processor configured to allocate slots of the discovery interval to
the plurality of other devices, wherein the second transceiver is
further configured to detect a discovery signal transmit
(TX)-beamformed by each of the plurality of other devices in the
slots and transmit feedback notifying a discovery signal detection
result to each of the plurality of other devices.
13. The device of claim 8, wherein the first transceiver is further
configured to transmit a signal notifying a list of at least one
other device for data sharing.
14. The device of claim 8, wherein the message comprises
information which represents a remaining time period until the band
switching is performed.
15. A device for supporting a first radio access technology (RAT)
and a second RAT, comprising: a first transceiver configured to
receive, by using the first RAT, a message to identify a start time
of a discovery interval for the second RAT, and to notify a band
switching; and a second transceiver configured to receive, by using
the second RAT, discovery signals during the discovery interval,
wherein the discovery signals are transmitted through a plurality
of beams, and wherein the first RAT provides a coverage that is
wider than the second RAT.
16. The device of claim 15, wherein the first transceiver is
further configured to receive information regarding at least one of
a discovery signal beamwidth and a number of beam sectors of the
discovery signal, by using the first RAT.
17. The device of claim 15, wherein the first transceiver is
further configured to transmit an acknowledgement (ACK) in response
to the received message.
18. The device of claim 15, wherein: the first transceiver is
further configured to receive allocation information of slots of
the discovery interval from a control device, and the second
transceiver is further configured to transmit discovery signals
TX-beamformed in different directions during a slot allocated to
the device and receive feedback notifying a discovery signal
detection result from the control device.
19. The device of claim 15, wherein the message comprises
information which represents a remaining time period until the band
switching is performed.
20. The device of claim 15, wherein the second transceiver is
further configured to transmitting a feedback signal indicating at
least one of the plurality of beams.
Description
CROSS-REFERENCE TO RELATED APPLICATION AND CLAIM OF PRIORITY
The present application is related to and claims benefit under 35
U.S.C. .sctn. 119(a) to a Korean patent application filed in the
Korean Intellectual Property Office on Apr. 2, 2015, and assigned
Serial No. 10-2015-0046905, the entire disclosure of which is
hereby incorporated by reference.
TECHNICAL FIELD
The present disclosure relates generally to link setup in a
wireless communication system.
BACKGROUND
To meet the demand for wireless data traffic having increased since
deployment of 4G communication systems, efforts have been made to
develop an improved 5G or pre-5G communication system. Therefore,
the 5G or pre-5G communication system is also called a `Beyond 4G
Network` or a `Post LTE System`. The 5G communication system is
considered to be implemented in higher frequency (mmWave) bands,
e.g., 60 GHz bands, so as to accomplish higher data rates. To
decrease propagation loss of the radio waves and increase the
transmission distance, the beamforming, massive multiple-input
multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array
antenna, an analog beam forming, large scale antenna techniques are
discussed in 5G communication systems. In addition, in 5G
communication systems, development for system network improvement
is under way based on advanced small cells, cloud Radio Access
Networks (RANs), ultra-dense networks, device-to-device (D2D)
communication, wireless backhaul, moving network, cooperative
communication, Coordinated Multi-Points (CoMP), reception-end
interference cancellation and the like. In the 5G system, Hybrid
FSK and QAM Modulation (FQAM) and sliding window superposition
coding (SWSC) as an advanced coding modulation (ACM), and filter
bank multi carrier (FBMC), non-orthogonal multiple access (NOMA),
and sparse code multiple access (SCMA) as an advanced access
technology have been developed.
The Internet, which is a human centered connectivity network where
humans generate and consume information, is now evolving to the
Internet of Things (IoT) where distributed entities, such as
things, exchange and process information without human
intervention. The Internet of Everything (IoE), which is a
combination of the IoT technology and the Big Data processing
technology through connection with a cloud server, has emerged. As
technology elements, such as "sensing technology", "wired/wireless
communication and network infrastructure", "service interface
technology", and "Security technology" have been demanded for IoT
implementation, a sensor network, a Machine-to-Machine (M2M)
communication, Machine Type Communication (MTC), and so forth have
been recently researched. Such an IoT environment may provide
intelligent Internet technology services that create a new value to
human life by collecting and analyzing data generated among
connected things. IoT may be applied to a variety of fields
including smart home, smart building, smart city, smart car or
connected cars, smart grid, health care, smart appliances and
advanced medical services through convergence and combination
between existing Information Technology (IT) and various industrial
applications.
In line with this, various attempts have been made to apply 5G
communication systems to IoT networks. For example, technologies
such as a sensor network, MTC, and M2M communication may be
implemented by beamforming, MIMO, and array antennas. Application
of a cloud Radio Access Network (RAN) as the above-described Big
Data processing technology may also be considered to be as an
example of convergence between the 5G technology and the IoT
technology.
In addition, thanks to advances in wireless communications, various
devices are wirelessly connected. Compared with wired connection,
the wireless connection offers various advantages, for example,
improved mobility, enhanced device design, low damage risk, and so
on. The wired connection can enable intuitive device connection
using a physical connector, whereas various standards of the
wireless connection cannot be distinguished with unaided eyes.
Further, an access process for the wireless connection differs per
standard, which can cause inconvenience to a user.
Hence, various technologies are under development in order to
lessen the inconvenience of the wireless connection and to
establish the wireless connection fast and intuitively. For
example, in Wireless Fidelity (Wi-Fi) connection, when tagging or
proximity is determined using Near Field Communications (NFC) or
Bluetooth Low Energy (BLE), the NFC or the BLE can exchange
necessary information for the Wi-Fi connection and conduct the fast
Wi-Fi connection. Such a technology is standardized by Application
Specific Platform (ASP) 2.0 Task Group (TG) of Wi-Fi Alliance
(WFA).
As discussed above, in link setup using a specific Radio Access
Technology (RAT), necessary information can be exchanged using
another RAT. In this case, since characteristics of the RATs are
different, a single process cannot support every combination of the
RATs. Hence, what is needed is an efficient access process in
consideration of the characteristics of the RAT.
SUMMARY
To address the above-discussed deficiencies it is a primary object
to provide an apparatus and a method for efficiently setting a link
using a plurality of Radio Access Technologies (RATs) in a wireless
communication system.
Another aspect of the present disclosure is to provide an apparatus
and a method for supporting an efficient connection process in
consideration of RAT characteristics in a wireless communication
system.
Yet another aspect of the present disclosure is to provide an
apparatus and a method for supporting a connection process in
consideration of RAT characteristics in a wireless communication
system.
Still another aspect of the present disclosure is to provide an
apparatus and a method for reducing energy consumption for link
setup in a wireless communication system.
A further aspect of the present disclosure is to provide an
apparatus and a method for setting a link using another RAT of a
different coverage in a wireless communication system.
A further aspect of the present disclosure is to provide an
apparatus and a method for synchronizing a discovery interval for a
second RAT using a first RAT in a wireless communication
system.
According to one aspect of the present disclosure, a method for
operating a device supporting a first RAT and a second RAT includes
sending information notifying a start time of a discovery interval
for the second RAT, using the first RAT, and sending discovery
signals during the discovery interval using the second RAT.
According to another aspect of the present disclosure, a method for
operating a device supporting a first RAT and a second RAT includes
receiving information notifying a start time of a discovery
interval for the second RAT, using the first RAT, and receiving a
discovery signal during the discovery interval using the second
RAT.
According to yet another aspect of the present disclosure, a device
for supporting a first RAT and a second RAT includes a first
communication module configured to send information notifying a
start time of a discovery interval for the second RAT, using the
first RAT, and a second communication module configured to send
discovery signals during the discovery interval using the second
RAT.
According to still another aspect of the present disclosure, a
device for supporting a first RAT and a second RAT includes a first
communication module configured to receive information notifying a
start time of a discovery interval for the second RAT, using the
first RAT, and a second communication module configured to receive
discovery signals during the discovery interval using the second
RAT.
Other aspects, advantages, and salient features of the invention
will become apparent to those skilled in the art from the following
detailed description, which, taken in conjunction with the annexed
drawings, discloses embodiments of the invention.
Before undertaking the DETAILED DESCRIPTION below, it may be
advantageous to set forth definitions of certain words and phrases
used throughout this patent document: the terms "include" and
"comprise," as well as derivatives thereof, mean inclusion without
limitation; the term "or," is inclusive, meaning and/or; the
phrases "associated with" and "associated therewith," as well as
derivatives thereof, may mean to include, be included within,
interconnect with, contain, be contained within, connect to or
with, couple to or with, be communicable with, cooperate with,
interleave, juxtapose, be proximate to, be bound to or with, have,
have a property of, or the like; and the term "controller" means
any device, system or part thereof that controls at least one
operation, such a device may be implemented in hardware, firmware
or software, or some combination of at least two of the same. It
should be noted that the functionality associated with any
particular controller may be centralized or distributed, whether
locally or remotely. Definitions for certain words and phrases are
provided throughout this patent document, those of ordinary skill
in the art should understand that in many, if not most instances,
such definitions apply to prior, as well as future uses of such
defined words and phrases.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present disclosure and its
advantages, reference is now made to the following description
taken in conjunction with the accompanying drawings, in which like
reference numerals represent like parts:
FIG. 1 illustrates devices for link setup in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 2 illustrates coverage difference of Radio Access Technologies
(RATs) in a wireless communication system according to an
embodiment of the present disclosure;
FIG. 3 illustrates a link setup process in a wireless communication
system according to an embodiment of the present disclosure;
FIG. 4 illustrates a broadcasting signal in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 5 illustrates discovery interval synchronization in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 6 illustrates a method for synchronizing a discovery interval
of a device which controls link setup in a wireless communication
system according to an embodiment of the present disclosure;
FIG. 7 illustrates a method for synchronizing a discovery interval
of a device which participates in link setup in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 8 illustrates discovery interval synchronization in a wireless
communication system according to another embodiment of the present
disclosure;
FIG. 9 illustrates a method for synchronizing a discovery interval
of a device which controls link setup in a wireless communication
system according to another embodiment of the present
disclosure;
FIG. 10 illustrates a method for synchronizing a discovery interval
of a device which participates in link setup in a wireless
communication system according to another embodiment of the present
disclosure;
FIG. 11 illustrates beam training of a discovery interval in a
wireless communication system according to an embodiment of the
present disclosure;
FIG. 12 illustrates a beam training method of a control device in a
wireless communication system according to an embodiment of the
present disclosure;
FIG. 13 illustrates a beam training method of a candidate device in
a wireless communication system according to an embodiment of the
present disclosure;
FIG. 14 illustrates reverse beam training in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 15 illustrates beam training of a discovery interval in a
wireless communication system according to another embodiment of
the present disclosure;
FIG. 16 illustrates a beam training method of a control device in a
wireless communication system according to another embodiment of
the present disclosure;
FIG. 17 illustrates a beam training method of a candidate device in
a wireless communication system according to another embodiment of
the present disclosure;
FIG. 18 illustrates reverse beam training in a wireless
communication system according to another embodiment of the present
disclosure;
FIG. 19 illustrates disabling of a communication module in a
wireless communication system according to an embodiment of the
present disclosure;
FIG. 20 illustrates operations of a control device in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 21 illustrates operations of a candidate device in a wireless
communication system according to an embodiment of the present
disclosure;
FIG. 22 illustrates a device in a wireless communication system
according to an embodiment of the present disclosure;
FIGS. 23A and 23B illustrate an interface for content sharing using
link setup according to an embodiment of the present
disclosure;
FIG. 24 illustrates a content sharing method using link setup
according to an embodiment of the present disclosure; and
FIGS. 25A through 25D illustrate interfaces displaying neighboring
devices in an electronic device according to an embodiment of the
present disclosure.
Throughout the drawings, like reference numerals will be understood
to refer to like parts, components and structures.
DETAILED DESCRIPTION
FIGS. 1 through 25D, discussed below, and the various embodiments
used to describe the principles of the present disclosure in this
patent document are by way of illustration only and should not be
construed in any way to limit the scope of the disclosure. Those
skilled in the art will understand that the principles of the
present disclosure may be implemented in any suitably arranged
device or system. The following description with reference to the
accompanying drawings is provided to assist in a comprehensive
understanding of embodiments of the invention as defined by the
claims and their equivalents. It includes various specific details
to assist in that understanding but these are to be regarded as
merely exemplary. Accordingly, those of ordinary skill in the art
will recognize that various changes and modifications of the
embodiments described herein can be made without departing from the
scope and spirit of the invention. In addition, descriptions of
well-known functions and constructions may be omitted for clarity
and conciseness.
The terms and words used in the following description and claims
are not limited to the bibliographical meanings, but, are merely
used by the inventor to enable a clear and consistent understanding
of the invention. Accordingly, it should be apparent to those
skilled in the art that the following description of embodiments of
the present disclosure is provided for illustration purpose only
and not for the purpose of limiting the invention as defined by the
appended claims and their equivalents.
It is to be understood that the singular forms "a," "an," and "the"
include plural referents unless the context clearly dictates
otherwise. Thus, for example, reference to "a component surface"
includes reference to one or more of such surfaces.
By the term "substantially" it is meant that the recited
characteristic, parameter, or value need not be achieved exactly,
but that deviations or variations, including for example,
tolerances, measurement error, measurement accuracy limitations and
other factors known to those of skill in the art, may occur in
amounts that do not preclude the effect the characteristic was
intended to provide.
Embodiments of the present disclosure provide an apparatus and a
method for efficiently setting a link using a plurality of Radio
Access Technologies (RATs) in a wireless communication system, and
more specifically, an apparatus and a method for achieving fast
connection and efficiency energy management between devices
supporting different RATs.
Hereinafter, terms indicating the RATs, terms indicating bands used
by the RATS, terms indicating devices, terms indicating signal
types, terms indicating resources or time intervals for the link
setup, and terms indicating connection states are described merely
by way of example. It should be understood that the present
disclosure is not limited to those terms and can adopt other
equivalent terms.
To ease the understanding, the present disclosure employs, but is
not limited to, terms and names defined in a particular
communication standard (e.g., Bluetooth Low Energy (BLE) or
Wireless Fidelity (Wi-Fi)). However, the present disclosure can be
equally applied to other standard systems.
To enhance connection efficiency using different RATs, electronic
devices can change link setup information of a RAT to use for data
communication, using another auxiliary RAT in advance. For example,
authentication information and Internet Protocol (IP) allocation
information required in the RAT for the data communication are
exchanged in advance, and thus a connection process can be
simplified and a connection time can be shortened. A band occupied
by the RAT for the data communication can be referred to as an
In-Band (TB), and a band occupied by the auxiliary RAT can be
referred to as an Out-Of-Band (OOB). Hereafter, the IB and the OOB
can indicate not only a physical frequency band but also the
corresponding RAT.
Wireless communication coverage is mostly related to signal
strength. Accordingly, it is common that, when the connection is
feasible in the OOB, IB connection is also allowed. That is, it is
presumed that the wireless communication coverage of the OOB is
similar to or smaller than the wireless communication coverage of
the D3. In a combination of some communication standards (e.g.,
Near Field Communications (NFC)/Bluetooth and Wi-Fi), it is
presumed that the coverage is similar or smaller.
However, when the D3 adopts a super high-speed RAT using a high
frequency, the above premise may not be valid. When the wireless
communication frequency rises, it is easy to secure a bandwidth and
thus a data rate can increase. However, due to characteristics of a
high-frequency signal, the wireless communication range, that is,
the coverage is generally narrowed. For example, compared with the
BLE using 2.4 GHz band, Wi-Fi Gigabites (WiGig) using 60 GHz band
is subject to a distance-based signal loss 100 times or more. In
addition, since signal diffraction or penetration degrades, the
communication is feasible only in limited situations.
The high-frequency wireless communication mostly performs
beamforming in order to overcome the signal loss. The beamforming
imposes directivity on the signal and thus increases a signal gain.
Hence, in the link setup, beam training for the beamforming may
need to be considered.
As such, it is difficult to maximize the link setup efficiency in
the IB of high-frequency or different coverage merely using the
information exchange using the OOB. Thus, the present disclosure
provides various embodiments for the link setup based on
interoperation between the IB and the OOB of high-frequency or
smaller coverage.
FIG. 1 depicts devices for link setup in a wireless communication
system according to an embodiment of the present disclosure. While
two devices 110 and 120 are disclosed in FIG. 1, three or more
devices can be employed.
Referring to FIG. 1, the device A 110 and the device B 120 can be
portable electronic devices, and can include one of a smart phone,
a portable terminal, a mobile phone, a mobile pad, a media player,
a tablet computer, a handheld computer, a Personal Digital
Assistant (PDA), an Access Point (AP), a printer, a camera, and
other electronic communication device, or a device combining two or
more functions of these devices. The device A 110 and the device B
120 can be smart home electronic devices, and can include one of a
Television (TV), a Personal Computer (PC), a speaker, a set-top
box, a console gaming device, and an electronic communication
device, or a device combining two or more functions of these
devices. The device A 110 includes a data communication module 112,
an auxiliary communication module 114, an access control processor
116, and a contents source 118. The device B 120 includes a data
communication module 122, an auxiliary communication module 124, an
access control processor 126, and a contents sink 128.
The device A 110 and the device B 120 can include a plurality of
wireless communication means and thus support a plurality of RATs.
The data communication modules 112 and 122 of the device A 110 and
the device B 120 support a second RAT using a high frequency, and
the auxiliary communication modules 114 and 124 support a first RAT
using a relatively low frequency. For example, the second RAT can
use 28 GHz, 39 GHz, 60 GHz, and 70 GHz bands, and the first RAT can
use 900 MHz, 2 GHz, 2.4 GHz, and 5 GHz bands. The device A 110 and
the device B 120 can transmit high-quality contents fast at a high
data rate through the data communication modules 112 and 122. By
contrast, the device A 110 and the device B 120 can exchange
control and management information with relatively low power
consumption through the auxiliary communication modules 114 and
124.
The access control processor 116 of the device A 110 can perform a
connection process based on interoperation of different RATs by
controlling the data communication module 112 and the auxiliary
communication module 114. Similarly, the access control processor
126 of the device B 120 can perform a connection process based on
the interoperation of different RATs by controlling the data
communication module 122 and the auxiliary communication module
124. The device A 110 and the device B 120 can store and play
contents using the contents source 118 and the contents sink
128.
FIG. 2 depicts coverage difference of RATs in a wireless
communication system according to an embodiment of the present
disclosure. In FIG. 2, a plurality of devices 110 and 120-1 through
120-5 is distributed.
Referring to FIG. 2, a user of the device A 110 wants to establish
a link with one or more of the devices 120-1 through 120-5 using
the device A 110. Coverage of the first RAT used for the
pre-communication is an auxiliary communication range 251, and
coverage of the second RAT used for the data communication is a
data communication range 253. That is, since the second RAT uses a
high frequency, the data communication range 253 is narrower than
the auxiliary communication range 251.
The device B1 120-1, the device B2 120-2, and the device B3 120-3
in the data communication range 253 can enable both of the data
communication and the auxiliary communication. However, the device
B4 120-4 and the device B5 120-5 can enable only the auxiliary
communication. Accordingly, the device A 110 can discover the
devices 120-1 through 120-5 as the connectable devices using the
first RAT but cannot perform the data communication with the device
B4 120-4 and the device B5 120-5 of the discovered devices using
the second RAT.
FIG. 3 illustrates a link setup process in a wireless communication
system according to an embodiment of the present disclosure.
Referring to FIG. 3, in operation 301, a device discovery phase
using a first RAT (e.g., BLE) is performed. The device A 110
discovers a neighboring device using the auxiliary communication
module 114 (e.g., a BLE module) and obtains a device list.
Referring back to FIG. 2, the devices 120-1 through 120-5 can be
discovered. That is, the operation 301 is a pre-discovery phase
using the auxiliary communication module 114. In various
embodiments, the operation 301 can be omitted and is supported only
in particular setting of subsequent processes. This is because a
relative communication range is limited due to the high frequency
of the data communication and thus the connection with the other
devices of the device list obtained in the operation 301 using the
second RAT is not ensured.
In operation 303, a band switching advertisement phase is
conducted. In the band switching advertisement phase, the device A
110 announces band switching using the auxiliary communication
module 114. That is, the device A 110 sends a signal notifying the
band switching. Other devices receiving the signal selectively
enable the data communication module 122. Referring back to FIG. 2,
all or some of the other devices 120-1 through 120-5 can enable the
data communication module 122 (e.g., a Wi-Fi module).
In operation 305, a discovery phase for the second RAT (e.g.,
high-frequency Wi-Fi) is conducted. In the discovery phase, the
device A 110 and the other devices 120-1 through 120-5 perform the
beamforming, and determine a beamforming map or a device map or
determine accessibility based on received signal strength. That is,
the device A 110 can perform the beam training on the other devices
120-1 through 120-5 and determine whether to set a link. The data
communication can be conducted in future with at least one
accessible device.
In operation 307, a data transfer and release phase is conducted.
In the data transfer and release phase, the user designates or
selects one or more other devices for the link setup in the device
list or through a User Interface (UI)/User Experience (UX) which
substitutes the list. Hence, the device A 110 sets a communication
link with the selected device and transfers contents according to
an executed service. In addition, the device A 110 can notify no
access to the other device residing outside the data communication
range or not selected, through the auxiliary communication module
114. In this case, the other device can disable the data
communication module 122.
In FIG. 3, the device A 110, which controls the discovery phase,
can be referred to as a control device. The other devices 120-1
through 120-5, which are connectable with the device A 110 using
the first RAT, are communication candidates using the second RAT,
and thus can be referred to as candidate devices. Since the other
devices 120-1 through 120-5 reside in the second RAT coverage and
share data with the device A 110, they can be referred to as
sharing devices.
The link setup procedure according to an embodiment shown in FIG. 3
cannot determine a time when user's intervention is available
merely using the auxiliary communication, that is, the second RAT
communication. This is because it is necessary to determine whether
to perform the data communication in consideration of
characteristics (e.g., short propagation distance, poor
penetration, diffraction, and the like) of the high-frequency
communication of the second RAT, and such a determination may need
to apply to a radio link using the second RAT for the data
communication. When the second RAT requires the beamforming, the
beamforming cannot be conducted using the first RAT. Further, when
the first RAT is used to locate the candidate devices 120 to
connect and to provide the location in response to a user's
selection, an additional operation of the data communication
module, that is, the communication module for the first RAT is
required prior to the user's intervention. Hence, the present link
setup process and its details are distinguished from the related
art.
Detailed operations of the band switching and the device discovery
for the data communication can affect the connection performance.
The band switching and the discovery are now explained.
The discovery process commences when the control device 110 sends a
broadcasting signal notifying the band switching using the first
RAT. The broadcasting signal can be referred to as a broadcasting
frame or a broadcasting message. The broadcasting signal includes
information notifying when to switch the band, and such information
is updated in every transmission with the remaining time until the
band switching. Hence, the control device 110 and the candidate
devices 120 can synchronize their timer for the discovery interval
using the second RAT.
For example, the broadcasting signal can include at least one of
parameters as shown in FIG. 4. FIG. 4 depicts a broadcasting signal
in a wireless communication system according to an embodiment of
the present disclosure. Referring to FIG. 4, the broadcasting
signal can include at least one of a length 471, a type 472, an
offset count 473, a Time Unit (TU) 474, personal identification
information 475, and a service attribute 476.
The length 471 indicates a length of the broadcasting signal, and
the type 472 indicates that the broadcasting signal is a frame or a
message notifying the band switching. The offset count 473 and the
TU 474 indicate the remaining time until the band switching. More
specifically, when the broadcasting signal is transmitted in every
TU, the offset count 473 reduces by one in every transmission and
the TU 474 indicates a time duration of one TU. The personal
identification information 475 is identification information of the
user of the control device 110 or the control device 110 sending
the broadcasting signal. The personal identification information
475 can be used for the candidate devices 120 to determine whether
to try the link setup with the control device 110. For example, the
personal identification information 475 can include a phone
number.
The service attribute 476 indicates an attribute of the service to
be initiated by the control device 110. For example, the service
attribute 476 can indicate at least one of whether a high data
transfer rate is needed, a security level, and an application to
initiate. The service attribute 476 can be used to variably operate
the beam search in the discovery phase, that is, in the operation
305 of FIG. 3. For example, when the service requires a high data
rate, the control device 110 can narrow a bandwidth to increase the
signal quality and sweep a plurality of beam sectors. When the
service requires a high security level, the control device 110 can
expand the bandwidth to reduce the signal transmission range and
sweep a small number of beam sectors.
Details of the discovery phase can vary depending on whether an
Acknowledgement (ACK) for the broadcasting signal is used or not.
Without using the ACK, the control device 110 repeatedly sends the
broadcasting signal for a preset number of times and then switches
the band. By contrast, using the ACK, the candidate devices 120
receiving the broadcasting signal respond with an ACK using another
broadcasting signal. The control device 110 can determine that all
of the candidate devices 120 respond by comparing the devices
sending the ACK with a list of the discovered or known devices,
suspend the broadcasting signal transmission, and thus save channel
resources.
As the number of the candidate devices 120 increases, the former
method without using the ACK is more advantageous. As the number of
the candidate devices 120 decreases, the latter method using the
ACK is more advantageous. Depending on a service or content sharing
range, the two methods are selectively operated. When the time for
the band switching arrives, the candidate devices 120 enable the
communication module for the second RAT and prepare a secondary
discovery process. In so doing, a guard time can be applied after
the band switching time by considering a timer error of the
candidate devices 120 or a delay in enabling the data communication
module.
The discovery process is now described in further detail by
referring to FIG. 5 and FIG. 8.
FIG. 5 depicts discovery interval synchronization in a wireless
communication system according to an embodiment of the present
disclosure. In FIG. 5, the ACK is not used.
Referring to FIG. 5, in operation 501, the control device 110
iteratively sends a band switching advertisement signal to the
candidate devices 120. The band switching advertisement signal can
include information indicating an offset. The offset indicates a
start of the discovery interval of the second RAT, that is, the
band switching timing. More specifically, the offset can indicate
the remaining time from the band switching advertisement signal
transmission time until the discovery interval starts. Since the
band switching advertisement signal is transmitted at regular time
intervals (e.g., 1TU), the offset reduces in every transmission.
Accordingly, the candidate devices 120 can receive at least one
band switching advertisement signal and thus confirm the discovery
interval start time. For example, the band switching advertisement
signal can include at least one of the parameters, specifically,
the length 471, the type 472, the offset count 473, the TU 474, the
personal identification information 475, and the service attribute
476 as shown in FIG. 4. Further, the band switching advertisement
signal can further include an indicator indicating whether the ACK
is used or not in response to the band switching advertisement
signal.
In operation 503, the control device 110 sends a beacon signal.
Before sending the beacon signal, the control device 110 can
allocate a guard time. The beacon signal is used to determine
connectivity using the second RAT and to determine an optimal beam.
The discovery and the beamforming using the beacon signal shall be
explained in detail by referring to FIG. 11 and FIG. 15.
FIG. 6 is a flowchart of a method for synchronizing a discovery
interval of a device which controls in link setup in a wireless
communication system according to an embodiment of the present
disclosure. FIG. 6 illustrates operations of the control device 110
for the process of FIG. 5.
Referring to FIG. 6, the control device sends a band switching
advertisement signal in operation 601. The band switching
advertisement signal is transmitted using a first RAT (e.g., BLE)
and indicates a discovery interval start time of the second RAT
(e.g., WiGig). For example, the discovery interval start time can
be expressed as an absolute or relative time value. For example,
the relative time value can include the remaining time from the
band switching advertisement signal transmission time until the
discovery interval start time. In addition, to determine whether to
set the link using the second RAT, the band switching advertisement
signal can further include identification information of the
device.
In operation 603, the control device determines whether a discovery
interval for the second RAT arrives. When the discovery interval
does not arrive, the control device returns to operation 601 and
repeatedly sends the band switching advertisement signal. In so
doing, when the discovery interval start time of the band switching
advertisement signal is represented as the relative time value, the
time value decreases from a previous time value.
By contrast, when the discovery interval arrives, the control
device performs the discovery for the second RAT in operation 605.
The first RAT and the second RAT use different frequencies, and the
coverage of the second RAT is narrower than the coverage of the
first RAT. Hence, although the band switching advertisement signal
is received, link setup success using the second RAT is not
ensured. Thus, the control device conducts the discovery using the
second RAT. For doing so, the control device can send beamformed
discovery signals.
FIG. 7 is a flowchart of a method for synchronizing a discovery
interval of a device which participates in link setup in a wireless
communication system according to an embodiment of the present
disclosure. FIG. 7 illustrates operations of one of the candidate
devices 120 for the process of FIG. 5.
Referring to FIG. 7, the candidate device receives a band switching
advertisement signal in operation 701. The band switching
advertisement signal is received using a first RAT (e.g., BLE) and
indicates a discovery interval start time of a second RAT (e.g.,
WiGig). For example, the discovery interval start time can be
expressed as an absolute or relative time value. For example, the
relative time value can include the remaining time from the band
switching advertisement signal transmission time until the
discovery interval start time. In addition, to determine whether to
set the link using the second RAT, the band switching advertisement
signal can further include identification information of the
control device which sends the band switching advertisement
signal.
In operation 703, the candidate device determines whether to set a
link. That is, the candidate device determines whether to
participate in the discovery process for the second RAT. According
to an embodiment of the present disclosure, the candidate device
can determine whether to set the link based on the identification
information of the band switching advertisement signal. More
specifically, the candidate device can determine based on the
identification information whether the control device is in a
predefined range. For example, when the identification information
is a phone number and a phone book contains the identification
information, the candidate device can determine to participate in
the discovery. According to another embodiment of the present
disclosure, the candidate device can determine whether to set the
link based on an application service to be initiated by the control
device. That is, each candidate device can preset whether to allow
the discovery in each application. For doing so, the control device
can provide application information using the band switching
advertisement signal. According to yet another embodiment of the
present disclosure, the candidate device can determine whether to
set the link based on proximity to the control device. In more
detail, the candidate device measures signal strength with the band
switching advertisement signal. When the signal strength exceeds a
threshold, the candidate device can determine to participate in the
discovery. According to still another embodiment of the present
disclosure, the candidate device can determine whether to set the
link according to a user's selection. For doing so, the candidate
device can display an interface asking about data communication
connectivity through a display means, and determine whether to
participate in the discovery according to a user's command.
According to a further embodiment of the present disclosure, the
candidate device can always determine to participate in the
discovery. In this case, the operation 703 can be omitted.
When determining to set the link, the candidate device synchronizes
the discovery interval for the second RAT in operation 705. That
is, based on the discovery interval start time information of the
band switching advertisement signal, the candidate device
determines the discovery interval start time. More specifically,
the candidate device can set a timer value according to the
remaining time from the band switching advertisement signal
transmission until the discovery interval start time, and drive the
timer.
In operation 707, the candidate device determines whether the
discovery interval for the second RAT arrives. When using the timer
for the discovery interval synchronization, the candidate device
determines whether the timer expires.
When the discovery interval arrives, the device performs the
discovery for the second RAT in operation 709. The first RAT and
the second RAT use different frequencies, and the coverage of the
second RAT is narrower than the coverage of the first RAT. Hence,
although the band switching advertisement signal is received, the
link setup success using the second RAT is not ensured. Thus, the
candidate device conducts the discovery using the second RAT. For
doing so, the candidate device can enable the communication module
for the second RAT and receive the beamformed discovery
signals.
FIG. 8 illustrates discovery interval synchronization in a wireless
communication system according to another embodiment of the present
disclosure, where the ACK is used.
Referring to FIG. 8, in operation 801, the control device 110
discovers the candidate devices 120. That is, the control device
110 determines a list of the candidate devices 120. The candidate
devices 120 are devices anticipated to send an ACK, and the list of
the candidate devices 120 is used to determine ACK reception
completion. According to an embodiment of the present disclosure,
the candidate devices 120 can be determined based on data
communication records in the IB using the second RAT (e.g., WiGig).
In this case, the control device 110 can determine devices
participating in the IB data communication as the candidate devices
120. According to another embodiment of the present disclosure, the
candidate devices 120 can be determined through the discovery in
the OOB using the first RAT (e.g., BLE). In this case, the control
device 110 can conduct the discovery using the first RAT and
determine the discovered devices as the candidate devices 120.
In operation 803, the control device 110 iteratively sends a band
switching advertisement signal to the candidate devices 120. The
band switching advertisement signal can include information
indicating an offset. The offset indicates a start of the discovery
interval of the second RAT, that is, the band switching time. More
specifically, the offset can indicate the remaining time from the
band switching advertisement signal transmission time until the
discovery interval start. Since the band switching advertisement
signal is transmitted at regular time intervals (e.g., 1TU), the
offset reduces in every transmission. Accordingly, the candidate
devices 120 can confirm the discovery interval start time. For
example, the band switching advertisement signal can include at
least one of the parameters, specifically, the length 471, the type
472, the offset count 473, the TU 474, and the personal
identification information 475 as shown in FIG. 4. Further, the
band switching advertisement signal can further include an
indicator indicating whether the ACK is used in response to the
band switching advertisement signal.
In operation 805, the control device 110 receives ACKs from all or
some of the candidate devices 120. The ACK informs the control
device 110 that the band switching advertisement signal is
received. The ACK can include a device name sending the ACK. For
example, the device name can include an identifier used in a first
RAT network or another identification information (e.g., a phone
number). Upon receiving the ACK, the control device 110 can
determine which one of the candidate devices 120 receives the band
switching advertisement signal. In FIG. 8, the control device 110
sends the band switching advertisement signal in the operation 803
and receives the ACK in the operation 805. Notably, the ACK is not
always received after the band switching advertisement signal is
transmitted, and can be received during the iterative transmission
of the band switching advertisement signal. For example, at least
one ACK can be received after the band switching advertisement
signal #1 is transmitted and before the band switching
advertisement signal #2 is transmitted. That is, the operation 803
and the operation 805 can be executed at the same time.
In operation 807, the control device 110 suspends the band
switching advertisement transmission. It is assumed that the ACKs
are received from all of the candidate devices 120 in the operation
805. Using the device name of the ACK, the control device 110 can
determine whether the ACK is received from each of the candidate
devices 120 of the candidate device list. When receiving the ACKs
from all of the candidate devices 120, the control device 110
determines that there is no need to transmit the band switching
advertisement signal any more. The control device 110 suspends the
band switching advertisement transmission, thus preventing
unnecessary power and resource waste.
FIG. 9 is a flowchart of a method for synchronizing a discovery
interval of a control device which controls in link setup in a
wireless communication system according to another embodiment of
the present disclosure. FIG. 9 illustrates operations of the
control device 110 for the process of FIG. 8.
Referring to FIG. 9, the control device determines candidate
devices in operation 901. The candidate devices are candidates
anticipated to send the ACK, and a list of the candidate devices is
used to determine ACK reception completion. According to an
embodiment of the present disclosure, the control device can
determine devices participating in the D3 data communication using
the second RAT (e.g., WiGig), as the candidate devices. According
to another embodiment of the present disclosure, the control device
can perform the discover process using the first RAT (e.g., BLE)
and determine the discovered devices as the candidate devices.
In operation 903, the control device sends a band switching
advertisement signal. The band switching advertisement signal is
transmitted using the first RAT and indicates a discovery interval
start time of the second RAT. For example, the discovery interval
start time can be expressed as an absolute or relative time value.
For example, the relative time value can include the remaining time
from the band switching advertisement signal transmission time
until the discovery interval start time. In addition, to determine
whether to set the link using the second RAT, the band switching
advertisement signal can further include identification information
of the device.
In operation 905, the control device determines whether ACKs are
received from all of the candidate devices. The control device
receives the ACK of the band switching advertisement signal, and
the ACK includes a device name of the candidate device sending the
ACK. Hence, the control device can determine whether ACKs are
received from all of the candidate devices by comparing the
candidate device list with the device name of the ACK.
When not receiving the ACKs from all of the candidate devices, the
control device determines whether the discovery interval for the
second RAT arrives in operation 907. When the discovery interval
does not arrive, the control device returns to operation 903 and
iteratively sends the band switching advertisement signal. In so
doing, when the discovery interval start time is a relatively time
value in the band switching advertisement signal, the time value
decreases from the previous transmission.
When receiving the ACKs from all of the candidate devices, the
control device determines whether the discovery interval for the
second RAT arrives in operation 909. Unlike the operation 907,
although the discovery interval does not arrive, the control device
does not return to operation 903 but stands by.
In operation 911, the control device performs the discovery for the
second RAT. The first RAT and the second RAT use different
frequencies, and the coverage of the second RAT is narrower than
the coverage of the first RAT. Hence, although the band switching
advertisement signal is received, the link setup success using the
second RAT is not ensured. Thus, the candidate device conducts the
discovery using the second RAT. For doing so, the candidate device
can transmit beamformed discovery signals.
FIG. 10 is a flowchart of a method for synchronizing a discovery
interval of a candidate device which participates in link setup in
a wireless communication system according to another embodiment of
the present disclosure. FIG. 10 illustrates operations of one of
the candidate devices 120 for the process of FIG. 8.
Referring to FIG. 10, the candidate device receives a band
switching advertisement signal in operation 1001. The band
switching advertisement signal is received using a first RAT (e.g.,
BLE) and indicates a discovery interval start time of a second RAT
(e.g., WiGig). For example, the discovery interval start time can
be expressed as an absolute or relative time value. For example,
the relative time value can include the remaining time from the
band switching advertisement signal transmission time until the
discovery interval start time. In addition, to determine whether to
set the link using the second RAT, the band switching advertisement
signal can further include identification information of a control
device which sends the band switching advertisement signal.
In operation 1003, the candidate device sends an ACK. The ACK
informs the control device that the band switching advertisement
signal is received. The ACK can include a name of the candidate
device. For example, the name can include an identifier used in the
first RAT network or another identification information (e.g., a
phone number).
In operation 1005, the candidate device determines whether to set a
link. That is, the candidate device determines whether to
participate in the discovery process for the second RAT. According
to an embodiment of the present disclosure, the candidate device
can determine whether to set the link based on the identification
information of the band switching advertisement signal. More
specifically, the candidate device can determine based on the
identification information whether the control device is in a
predefined range. For example, when the identification information
is a phone number and a phone book contains the identification
information, the candidate device can determine to participate in
the discovery. According to another embodiment of the present
disclosure, the candidate device can determine whether to set the
link based on proximity to the control device. In more detail, the
candidate device measures signal strength with the band switching
advertisement signal. When the signal strength exceeds a threshold,
the candidate device can determine to participate in the discovery.
According to yet another embodiment of the present disclosure, the
candidate device can determine whether to set the link based on a
user's selection. For doing so, the candidate device can display an
interface asking about data communication connectivity through a
display means, and determine whether to participate in the
discovery according to a user's command. According to still another
embodiment of the present disclosure, the candidate device can
always determine to participate in the discovery. In this case, the
operation 1005 can be skipped.
When determining to set the link, the candidate device synchronizes
the discovery interval for the second RAT in operation 1007. That
is, based on the discovery interval start time information of the
band switching advertisement signal, the candidate device
determines the discovery interval start time. More specifically,
the candidate device can set a timer value according to the
remaining time from the band switching advertisement signal
transmission until the discovery interval start time, and drive the
timer.
In operation 1009, the candidate device determines whether the
discovery interval for the second RAT arrives. When using the timer
for the discovery interval synchronization, the candidate device
determines whether the timer expires.
When the discovery interval arrives, the device performs the
discovery for the second RAT in operation 1011. The first RAT and
the second RAT use different frequencies, and the coverage of the
second RAT is narrower than the coverage of the first RAT. Hence,
although the band switching advertisement signal is received, the
link setup success using the second RAT is not ensured. Thus, the
candidate device conducts the discovery using the second RAT. For
doing so, the candidate device can enable the communication module
for the second RAT and receive the beamformed discovery
signals.
As such, the devices enable the data communication module at a
particular time and operate in a discovery mode.
When the discovery interval is not synchronized, the control device
which conducts the beamforming performs Sector Sweep (SS) on a
beacon frame in all directions, and then the candidate devices 120
sequentially perform the SS on a Sector Sweep (SSW) frame in a
reverse direction. In so doing, the devices receiving the frame set
a receive (RX) beam direction to an omni direction or a quasi-omni
direction, select a beam sector of best reception quality, and
notify the selected beam sector to a counterpart device. Since a
plurality of devices compete for the SS of the SSW frame,
concurrent attempts can cause a collision. Hence, unexpected time
delay and energy consumption can arise.
However, the present discovery interval synchronization can achieve
more efficient beamforming, that is, beam training. The present
devices synchronize the discovery interval using the band switching
broadcasting signal through the auxiliary communication module.
Likewise, when the control device which conducts the beamforming
performs the SS on beacon frames in the omni direction, all of the
candidate devices 120 concurrently receive the beacon frames. Next,
the control device iteratively sends the beacon frame in the omni
direction or the quasi-omni direction. In so doing, the candidate
devices 120 receive the beacon frames by sector-sweeping the RX
beam and select a beam sector of best signal quality. In this case,
merely two SSs can finish the concurrent beamforming of the
candidate devices 120.
Such a discovery process based on the synchronization can be far
more advantageous in a direct connection between devices. In the
discovery process without the synchronization, the control device
which forms the beam and the candidate devices 120 each perform the
transmit (TX) beam training and thus an optimal beam for the
omni-directional communication is not selected. However, in the
discovery process based on the synchronization, the control device
performs the TX beam training and the candidate devices 120 conduct
the RX beam training, thus selecting an optimal beam for content
delivery from the control device to the candidate devices 120.
Typically, in content sharing between devices, a device initiating
the connection has contents and forms the beam. Hence, in most
cases, an optimal beam can be selected. Such a discovery process
based on the synchronization can be fulfilled as shown in FIG.
11.
FIG. 11 is a flowchart of beam training of a discovery interval in
a wireless communication system according to an embodiment of the
present disclosure. In FIG. 11, a control device, that is, the
control device 110 finishes the beam training through two SSs.
Referring to FIG. 11, during a first interval, the control device
110 performs TXSS. That is, the control device 110 beamforms beacon
signals in supportable beam directions and sequentially sends the
beamformed beacon signals 1101-1 through 1101-N. In so doing, all
of the candidate devices 120 stand by in a listen state. That is,
the candidate devices 120 try to detect the beamformed beacon
signals 1101-1 through 1101-N. The candidate devices 120 receive
the beacon signals 1101-1 through 1101-N over an omni-directional
RX beam without the RX beamforming. Accordingly, the candidate
devices 120 each can determine an optimal TX beam. Notably, based
on the coverage of the second RAT, some of the candidate devices
120 may not detect all of the beacon signals 1101-1 through
1101-N.
During a second interval, the control device 110 sequentially
transmits beacon signals 1103-1 through 1103-N over an
omni-directional beam. In so doing, the candidate devices 120
perform the RX beamforming. That is, the candidate devices 120
conduct the RXSS. Hence, the candidate devices 120 each can
determine an optimal RX beam. Notably, based on the coverage of the
second RAT, some of the candidate devices 120 may not detect all of
the beacon signals 1103-1 through 1103-N.
Next, the candidate devices 120 each send feedback information
notifying the optimal TX beam and the optimal RX beam. Yet, some of
the candidate devices 120, some not detecting the beacon signals
1101-1 through 1101-N, do not transmit the feedback information.
The feedback information can include at least one of information
indicating the optimal TX beam, information indicating the optimal
RX beam, and channel quality of a combination of the optimal TX
beam and the optimal RX beam. Hence, the control device 110 can
determine whether to set the link with the candidate devices 120
using the second RAT. For example, the control device 110 can
determine to set the link with the candidate device which sends the
feedback information. Alternatively, the control device 110 can
determine to set the link with the candidate device which reports
the channel quality over a threshold.
FIG. 12 is a flowchart of a beam training method of a control
device in a wireless communication system according to an
embodiment of the present disclosure. FIG. 12 illustrates
operations of the control device 110 for the process of FIG.
11.
Referring to FIG. 12, in operation 1201, the control device
transmits beamformed discovery signals in a first interval. The
discovery signal can be referred to as a beacon frame. The
discovery signal can include at least one of a timestamp, a beacon
interval, capability information of the control device, and a
service set identifier.
In operation 1203, the control device sends omni-directional
training signals during a second interval. That is, the control
device sends the training signals not beamformed, that is, over the
omni-directional beam. The training signal can be constructed
identically to or differently from the discovery signal.
In operation 1205, the control device receives feedback. The
feedback can be received from at least one of the candidate devices
receiving a band switching advertisement signal using the first
RAT. That is, the feedback is received from at least one of the
candidate devices, which detects the discovery signal and the
training signal. The feedback can include at least one of
information indicating an optimal TX beam of a corresponding
device, information indicating an optimal RX beam of the
corresponding device, and channel quality of a combination of the
optimal TX beam and the optimal RX beam. Herein, the feedback can
be received using the first RAT or the second RAT.
In operation 1207, the control device determines a communicable
device and an optimal beam. That is, the control device can
determine whether to set the link with the candidate devices using
the second RAT. For example, the control device can determine to
set the link with the candidate device which sends the feedback
information. Alternatively, the control device can determine to set
the link with the candidate device which reports the channel
quality over a threshold.
In FIG. 12, the control device transmits the discovery signals and
the training signals in the operation 1201 and the operation 1203.
According to another embodiment of the present disclosure, the
control device can dynamically transmit the discovery/training
signal based on signal strength of the second RAT or the service
attribute 476 of FIG. 4. For example, when the signal strength of
the second RAT is high or exceeds a predefined threshold, the
control device can relatively widen a beamwidth and reduce the
number of sectors. In this case, the time taken for the beam
training and the power consumption of the control device can
reduce. When a plurality of signal values is measured in relation
to the first RAT, the control device can adjust the beamwidth based
on the smallest signal value. For example, when the service
attribute 476 requires a high transfer rate, the control device can
relatively narrow the beamwidth to enhance the signal quality and
sweep a plurality of beam sectors. By contrast, when the service
requires a high security level, the control device can relatively
widen the beamwidth to narrow the signal propagation range and
sweep a relatively small number of beam sectors. When the beamwidth
is adjustable, information about at least one of the beamwidth and
the number of the beam sectors can be contained in the
discovery/training signal transmitted in the operation 1201.
FIG. 13 is a flowchart of a beam training method of a candidate
device in a wireless communication system according to an
embodiment of the present disclosure. FIG. 13 illustrates
operations of one of the candidate devices 120 for the process of
FIG. 11.
Referring to FIG. 13, in operation 1301, the candidate device
detects a beamformed discovery signal during the first interval. In
the first interval, the control device sequentially transmits the
discovery signals beamformed in different directions. The candidate
device tries to detect the discovery signal without RS beamforming
and thus detects at least one discovery signal. The beam direction
of the at least one discovery signal detected is an optimal TX beam
for the candidate device. The discovery signal can be referred to
as a beacon frame. The discovery signal can include at least one of
a timestamp, a beacon interval, capability information of the
control device, and a service set identifier.
In operation 1303, the candidate device detects a training signal
through the RX beamforming during the second interval. In the
second interval, the control device iteratively transmits the
training signals not beamformed, that is, over an omni-directional
beam. The candidate device tries to detect the training signal over
RX beams of different directions, and thus detects at least one
training signal. The beam direction of the at least one discovery
signal detected is an optimal RX beam for the candidate device.
In operation 1305, the candidate device sends feedback. The
feedback can include at least one of information indicating the
optimal TX beam, information indicating the optimal RX beam, and
channel quality of a combination of the optimal TX beam and the
optimal RX beam.
In FIG. 13, the candidate device receives the discovery/training
signals in the operation 1301 and the operation 1303. According to
another embodiment of the present disclosure, the control device
can adjust the beamwidth of the discovery/training signals. That
is, when the control device dynamically operates the beam training,
the candidate device can receive information about at least one of
the beamwidth and the number of the beam sectors in operation 1201
and adaptively conduct the beam training according to the received
information.
In FIGS. 11, 12, and 13, the control device determines the optimal
TX beam and the candidate device determines the optimal RX beam.
Accordingly, an optimized radio link can be attained for the data
transmission of the control device and the data reception of the
candidate device. Conversely, when the candidate device transmits
data to the control device, reciprocity is generally established.
Hence, the RX beam of the candidate device can be used as the TX
beam and the TX beam of the control device can be used as the RX
beam. However, when the reciprocity is not established, the RX beam
cannot be used as the TX beam and vice versa. In this case, when
one or more of the candidate devices are selected for the data
sharing, the control device and the selected device can perform
reverse beam training. For example, the reverse beam training can
be fulfilled as shown in FIG. 14.
FIG. 14 depicts reverse beam training in a wireless communication
system according to an embodiment of the present disclosure. FIG.
14 depicts the reverse beam training between the control device 110
and the candidate device 120-1. When a plurality of candidate
devices is selected, the process of FIG. 14 can be iteratively
applied to the candidate devices.
Referring to FIG. 14, during a first interval, the candidate device
120-1 performs TXSS. That is, the candidate device 120-1 beamforms
beacon signals in supportable beam directions and sequentially
transmits the beamformed beacon signals 1401-1 through 1401-N. In
so doing, the control device 110 stands by in a listen state. That
is, the control device 110 tries to detect the beamformed beacon
signals 1401-1 through 1401-N. The control device 110 receives the
beacon signals 1401-1 through 1401-N over an omni-directional RX
beam without RX beamforming. Hence, the control device 110 can
determine an optimal TX beam of a reverse link. Yet, depending on
the coverage of the second RAT, the control device 110 may not
detect all of the beacon signals 1401-1 through 1401-N. During a
second interval, the candidate device 120-1 sequentially sends
beacon signals 1403-1 through 1403-N in sequence over an
omni-directional beam. In so doing, the control device 110 performs
RX beamforming. That is, the control device 110 conducts RXSS.
Thus, the control device 110 can determine an optimal RX beam of
the reverse link. Next, the control device 110 sends feedback
information notifying the optimal TX beam and the optimal RX beam.
The feedback information can include at least one of information
indicating the optimal TX beam, information indicating the optimal
RX beam, and channel quality of a combination of the optimal TX
beam and the optimal RX beam.
In FIGS. 11, 12, and 13, the control device 110 conducts the SS
twice. According to another embodiment of the present disclosure,
the discovery can be carried out such that the control device 110
conducts the SS once and the candidate devices 120 each perform the
SS. In this case, the devices can control collisions by scheduling
SS intervals of the candidate devices 120 in advance using the
auxiliary communication module. The discovery including the
scheduling is now explained in FIG. 15.
FIG. 15 depicts beam training of a discovery interval in a wireless
communication system according to another embodiment of the present
disclosure. In FIG. 15, the beam training is completed through SS
of a control device, that is, the control device 110 and scheduled
SS of candidate devices 120, that is, the candidate devices
120.
Referring to FIG. 15, the control device 110 and the candidate
devices 120 perform slot allocation. For example, the control
device 110 allocates slots of a second interval to the candidate
devices 120. The control device 110 notifies a slot allocation
result to the candidate devices 120. The slot allocation result can
be delivered by a broadcasting signal. The control device 110 can
transmit the slot allocation result using the first RAT. The slot
allocation can be referred to as a band enabling negotiation
phase.
Next, the control device 110 conducts TXSS during the first
interval. That is, the control device 110 beamforms beacon signals
in supportable beam directions and transmits the beamformed beacon
signals 1501-1 through 1501-N in sequence. The candidate devices
120 all stand by in a listen state. That is, the candidate devices
120 try to detect the beamformed beacon signals 1501-1 through
1501-N. In so doing, the candidate devices 120 receive the beacon
signals 1501-1 through 1501-N over an omni-directional RX beam
without RX beamforming. Hence, the candidate devices 120 each can
determine an optimal TX beam. Although not depicted in FIG. 15, the
candidate devices 120 each can feed information notifying the
optimal TX beam back. Yet, depending on the coverage of the second
RAT, some of the candidate devices 120 may not detect all of the
beacon signals 1501-1 through 1501-N.
During a second interval, the candidate devices 120 each perform
TXSS in their allocated slot. The control device 110 receives
training signals from the candidate devices 120 over an
omni-directional RX beam without RX beamforming, and then sends
feedback information to the corresponding candidate device at a
back end of each slot. Herein, the feedback information can be
transmitted without being beamformed, that is, over an
omni-directional beam. More specifically, a first candidate device
beamforms training signals in supportable beam directions and
sequentially transmits the beamformed training signals 1503-1
through 1503-M, and the control device 110 sends feedback
information 1505 to the first candidate device. A second candidate
device beamforms training signals in supportable beam directions
and sequentially transmits the beamformed training signals 1507-1
through 1507-M, and the control device 110 sends feedback
information 1509 to the second candidate device. The feedback
information 1505 and the feedback information 1509 include
information notifying an optimal beam determined by the control
device 110. Since similarity of the TX beam and the RX beam is
recognized based on channel reciprocity, the candidate devices 120
each can determine the optimal RX beam based on the feedback
information.
FIG. 16 is a flowchart of a beam training method of a control
device in a wireless communication system according to another
embodiment of the present disclosure. FIG. 16 illustrates
operations of the control device 110 for the process of FIG.
15.
Referring to FIG. 16, the control device allocates slots of a
second interval of a discovery interval to candidate devices and
notifies a slot allocation result in operation 1601. The control
device can send the slot allocation information using a
broadcasting signal. The slot is a segmented resource unit of the
second interval on a time axis, and one slot occupies a resource
for delivering a plurality of training signals and feedback
information. The slot allocation result can be notified using
combinations of a slot number and a device name. The control device
can transmit the slot allocation result using a first RAT (e.g.,
BLE).
In operation 1603, the control device sends beamformed discovery
signals during a first interval. The discovery signal can be
referred to as a beacon frame. The discovery signal can include at
least one of a timestamp, a beacon interval, capability information
of the control device, and a service set identifier.
In operation 1605, the control device detects a beamformed training
signal in an m-th slot of the second interval. During the m-th
slot, one of the candidate devices iteratively sends training
signals beamformed. Herein, m is initially 1. The control device
tries to detect the training signal without RX beamforming and thus
detects at least one training signal. A beam direction applied to
the at least one training signal detected is an optimal RX beam of
the candidate device. In addition, the control device can measure
channel quality.
In operation 1607, the control device sends feedback. The feedback
can include information indicating the optimal RX beam. That is,
the control device notifies the optimal RX beam identified in the
operation 1605, to the corresponding candidate device. The control
device can send the feedback without beamforming, that is, using an
omni-directional beam. Alternatively, the control device can send
the feedback over an optimal TX beam of the corresponding candidate
device.
In operation 1609, the control device determines whether all of the
slots are completely processed. That is, the control device
determines whether the training signal is detected in all of the
slots allocated in the operation 1601. When not completely
processing all of the slots, the control device increases m by one
in operation 1611 and then returns to the operation 1605.
By contrast, when completely processing all of the slots, the
control device determines a communicable device and an optimal beam
in operation 1613. That is, the control device can determine
whether to set a link with the candidate devices using a second RAT
(e.g., WiGig). For example, the control device can determine to set
the link with the candidate device which sends the training signal
detected in the operation 1605. Alternatively, the control device
can determine to set the link with the candidate device of the
channel quality over a threshold.
FIG. 17 is a flowchart of a beam training method of a candidate
device in a wireless communication system according to another
embodiment of the present disclosure. FIG. 17 illustrates
operations of one of the candidate devices 120 for the process of
FIG. 15.
Referring to FIG. 17, the candidate device confirms allocation of
slots of a second interval of a discovery interval in operation
1701. That is, the candidate device receives a slot allocation
result from a control device. The slot is a segmented resource unit
of the second interval on a time axis, and one slot occupies a
resource for delivering a plurality of training signals and
feedback information. The slot allocation result can be notified
using combinations of a slot number and a device name. The
candidate device can receive the slot allocation result using a
first RAT (e.g., BLE).
In operation 1703, the candidate device detects a beamformed
discovery signal during a first interval. During the first
interval, the control device sequentially transmits the beamformed
training signals in different directions. The candidate device
tries to detect the discovery signal without RX beamforming and
detects at least one discovery signal. A beam direction applied to
the at least one training signal detected is an optimal TX beam of
the candidate device. The discovery signal can be referred to as a
beacon frame. The discovery signal can include at least one of a
timestamp, a beacon interval, capability information of the control
device, and a service set identifier. In addition, the candidate
device can send feedback notifying the optimal TX beam to the
control device.
In operation 1705, the candidate device determines whether its
allocated slot arrives in the second interval. That is, the
candidate device is allocated one of the slots of the second
interval. Hence, the candidate device may not perform the discovery
in a slot allocated to other candidate device.
When the allocated slot comes, the candidate device transmits
beamformed training signals during the allocated slot in operation
1707. That is, the candidate device beamforms the training signals
in supportable beam directions and sends the beamformed training
signals in sequence.
In operation 1709, the candidate device receives feedback from the
control device. The feedback can include information indicating an
optimal RX beam for the candidate device determined by the control
device. The candidate device can receive the feedback without
beamforming, that is, over an omni-directional beam.
In FIGS. 15, 16, and 17, the control device determines the optimal
TX beam and the optimal RX beam. Accordingly, an optimized radio
link can be attained for the data transmission of the control
device and the data reception of the candidate device. Conversely,
when the candidate device transmits data to the control device,
reciprocity is generally established. Hence, the RX beam of the
candidate device can be used as the TX beam and the TX beam of the
control device can be used as the RX beam. However, when the
reciprocity is not established, the RX beam cannot be used as the
TX beam and vice versa. In this case, when one or more of the
candidate devices are selected for data sharing, the control device
and the selected device can perform reverse beam training. For
example, the reverse beam training can be fulfilled as shown in
FIG. 18.
FIG. 18 depicts reverse beam training in a wireless communication
system according to another embodiment of the present disclosure.
FIG. 18 depicts reverse beam training between the control device
110 and the candidate device 120-1. When a plurality of candidate
devices is selected, the process of FIG. 18 can be iteratively
applied to the candidate devices.
Referring to FIG. 18, the candidate device 120-1 performs TXSS
during a first interval. That is, the candidate device 120-1
beamforms beacon signals in supportable beam directions and
sequentially transmits the beamformed beacon signals 1801-1 through
1801-N. In so doing, the control device 110 stands by in a listen
state. That is, the control device 110 tries to detect the
beamformed beacon signals 1801-1 through 1801-N. The control device
110 receives the beacon signals 1801-1 through 1801-N over an
omni-directional RX beam without RX beamforming. Hence, the control
device 110 can determine an optimal TX beam of a reverse link.
Although not depicted in FIG. 18, the control device 110 can feed
information notifying the optimal TX beam back. Next, the control
device conducts TXSS during a second interval. The candidate device
120-1 receives a training signal from the control device 110 over
an omni-directional RX beam without RX beamforming and then sends
feedback information to the control device 110. Herein, the
feedback information can be transmitted without beamforming, that
is, over the omni-directional beam. More specifically, the
candidate device 120-1 beamforms training signals in supportable
beam directions, sequentially transmits the beamformed training
signals 1803-1 through 1803-N, and transmits feedback information
1805 to the control device 110.
As above, the devices can determine the communication over the
synchronized discovery interval and the optimal beam. Further, the
present disclosure allows a user having no intention of sharing
contents to selectively respond to a band switching request. Thus,
it is possible to prevent energy waste due to user's unnecessary
device enabling and to block user's location information from being
exposed to an unintended user in some cases.
The selective response to the band switching request can be
achieved by pre-defining a communication module enabling range for
the second RAT. For example, the device can restrict the range,
rather than permitting every request, to a case where a request is
received from a user of a stored contact, a case where proximity is
determined, or a case where the user selects the permission. In so
doing, information for the pre-determination can be exchanged or
acquired through the auxiliary communication module, that is, the
communication module for the first RAT.
Further, when devices not setting a data link enable the
communication module for the second RAT, a process for disabling
the communication module is required. For doing so, the control
device 110 can send a list of devices discovered in the IB and a
list of devices selected for the link setup to the candidate
devices 120 using the auxiliary communication module. The
communication module for the second RAT can be disabled as shown in
FIG. 19.
FIG. 19 depicts disabling of a communication module in a wireless
communication system according to an embodiment of the present
disclosure. In FIG. 19, devices belonging to a device set A 130 are
selected from the candidate devices 120, and data communication
modules of devices belonging to a device set B 140 are
disabled.
Referring to FIG. 19, a discovery phase for a second RAT (e.g.,
WiGig) is performed in operation 1901. For example, the discovery
phase can be conducted as shown in FIG. 11 or FIG. 15. Thus, the
control device 110 can determine communicable devices among the
candidate devices 120.
In operation 1903, the control device 110 selects at least one
device for data communication. The control device 110 selects at
least one of the communicable devices using the second RAT. For
example, the control device 110 can select at least one device
according to a predefined rule or a user's selection. Herein, the
device set A 130 is selected.
In operation 1905, the control device 110 sends a negotiation
advertisement signal to the device set A 130 and the device set B
140. The negotiation advertisement includes identification
information of at least one device for the data communication using
the second RAT. The negotiation advertisement includes
identification information of devices of the device set A 130.
Herein, the negotiation advertisement signal is transmitted using
the first RAT. For example, the negotiation advertisement signal
can be carried by a BLE advertisement frame.
In operation 1907, the devices of the device set B 140 disable
their communication module for the second RAT. That is, the devices
of the device set B 140 can control to turn off the communication
module for the second RAT or to change the communication module for
the second RAT into a sleep state. Yet, for other purposes than the
communication with the control device 110, the devices of the
device set B 140 can keep the communication module for the second
RAT enabled.
In operation 1909, the control device 110 transmits data to the
devices of the device set A 130. The data is transmitted using the
second RAT. More specifically, the control device 110 beamforms a
signal including the data and then transmits the beamformed signal.
The data can be unicast, multicast, or broadcast.
FIG. 20 illustrates operations of a control device in a wireless
communication system according to an embodiment of the present
disclosure. The control device supports a first RAT and a second
RAT. Compared with the first RAT, the second RAT uses a higher
frequency. The first RAT can consume less power than the second
RAT.
Referring to FIG. 20, in operation 2001, the control device
transmits information notifying a discovery interval start time for
the second RAT, using the first RAT. The information notifying the
discovery interval start time is delivered by a first RAT
broadcasting signal, and the broadcasting signal can further
include personal identification information of the control device.
For example, the information notifying the discovery interval start
time includes at least one parameter indicating a remaining time
from the information transmission until the start time. The
information notifying the discovery interval start time can be
iteratively transmitted. In this case, the information notifying
the discovery interval start time decreases in every
transmission.
In operation 2003, the control device transmits a discovery signal
during the discovery interval using the second RAT. Herein, the
discovery signal can be a beacon frame. The discovery interval
includes a first interval and a second interval. During the first
interval, the control device transmits TX-beamformed signals in a
plurality of directions. In the first interval, a plurality of
candidate devices is in a listen state. During the second interval,
the control device transmits the discovery signal using an
omni-directional beam. According to another embodiment of the
present disclosure, in the second interval, the control device can
detect signals TX-beamformed by the candidate devices, without
sending the discovery signals. In this case, the control device can
distribute slots of the second interval to the candidate devices
and receive signals from corresponding candidate devices in the
slots. Further, the control device can send feedback notifying the
detection result to the corresponding candidate device in each
slot. Herein, the slots can be allocated prior to the operation
2003, and the allocation result is transmitted using the first
RAT.
Although not depicted in FIG. 20, the control device can transmit
the information indicating the discovery interval start time and
then receive an ACK from at least one candidate device. In this
case, when receiving ACKs from all of the candidate devices, the
control device can suspend the transmission of the information
indicating the discovery interval start time. For doing so, the
control device can determine the candidate devices prior to the
operation 2001. For example, the control device can determine the
candidate devices by conducting the discovery process using the
first RAT or identifying data sharing devices using the second
RAT.
Although not depicted in FIG. 20, after the operation 2003, the
control device can send a signal notifying a list of at least one
candidate device for data sharing. In this case, some devices not
included in the list among the candidate devices can avoid
unnecessary power consumption by disabling the communication module
for the second RAT.
FIG. 21 illustrates operations of a candidate device in a wireless
communication system according to an embodiment of the present
disclosure. The candidate device supports a first RAT and a second
RAT. Compared with the first RAT, the second RAT uses a higher
frequency. The first RAT can consume less power than the second
RAT.
Referring to FIG. 21, in operation 2101, the candidate device
receives information indicating a discovery interval start time for
the second RAT, using the first RAT. The control device sends the
information indicating the discovery interval start time using a
first RAT broadcasting signal, and the broadcasting signal can
further include personal identification information of the control
device. For example, the information notifying the discovery
interval start time includes at least one parameter indicating a
remaining time from the information transmission until the start
time. The information notifying the discovery interval start time
can be iteratively transmitted. In this case, the information
notifying the discovery interval start time decreases in every
transmission.
In operation 2103, the candidate device receives a discovery signal
during the discovery interval using the second RAT. Herein, the
discovery signal can be a beacon frame. The discovery interval
includes a first interval and a second interval. During the first
interval, the candidate device detects one of signals TX-beamformed
by the control device in a plurality of directions. In the first
interval, a plurality of devices including the candidate device is
in a listen state. During the second interval, the candidate device
detects at least one of discovery signals received from the control
device over an omni-directional beam. According to another
embodiment of the present disclosure, during the second interval,
the candidate device can send the discovery signals TX-beamformed
to different directions in its allocated slot, without detecting
the discovery signals. In this case, the candidate device can
receive the slot allocation result of the second interval from the
control device. Further, the candidate device can receive from the
control device feedback notifying the detection result of the
signals transmitted to the candidate device. Herein, the slots can
be allocated prior to the operation 2103, and the allocation result
is transmitted using the first RAT.
Although not depicted in FIG. 21, the candidate device can receive
the information indicating the discovery interval start time and
then send the ACK to the control device. The ACK can include
identification information of the candidate device.
Unlike the method of FIG. 21, the candidate device may not detect
the discovery signal in operation 2103. In this case, the candidate
device can receive a signal notifying a list of at least one
candidate device for sharing data, from the control device using
the first RAT. When the candidate device is not included in the
list, the candidate device can disable the communication module for
the second RAT and thus avoid unnecessary power consumption.
FIG. 22 is a block diagram of a device in a wireless communication
system according to an embodiment of the present disclosure.
Hereinafter, a term such as a unit, a part, or like, represents a
unit for processing at least one function or operation, and can be
implemented using hardware alone or hardware in combination with
software.
Referring to FIG. 22, the device includes a communication unit
2210, a storage unit 2220, and a control unit 2230.
The communication unit 2210 sends and receives signals over a radio
channel. For example, the communication unit 2210 converts a
baseband signal to a bit string and vice versa according to a
physical layer standard of the system. For the data transmission,
the communication unit 2210 generates complex symbols by encoding
and modulating a transmit bit string. In data reception, the
communication unit 2210 restores the received bit string by
demodulating and decoding the baseband signal. The communication
unit 2210 up-converts the baseband signal to a Radio Frequency (RF)
signal, transmits the RF signal over an antenna, and down-converts
an RF signal received over the antenna to a baseband signal. For
example, the communication unit 2210 can include a transmit filter,
a receive filter, an amplifier, a mixer, an oscillator, a Digital
to Analog Converter (DAC), and an Analog to Digital Converter
(ADC).
The communication unit 2210 can include a plurality of RF chains.
The communication unit 2210 can conduct the beamforming. For the
beamforming, the communication unit 2210 can adjust a phase and an
amplitude of signals transmitted and received via a plurality of
antennas or antenna elements. The communication unit 2210 can
include a plurality of communication modules 2212 and 2214 for
supporting different RATs. Also, the communication unit 2210 can
include different communication modules 2212 and 2214 for
processing signals of different frequency bands. For example, the
first module 2212 supports a first RAT, and the second module 2214
supports a second RAT. The second RAT uses a higher frequency than
the first RAT. For example, the different RATs can include NFC,
BLE, Wi-Fi, WiGig, cellular networks (e.g., Long Term Evolution
(LTE)), and the like. The different frequency bands can include
Super High Frequency (SHF) band (e.g., 2.5 GHz, 5 GHz) and
millimeter (mm) wave band (e.g., 60 GHz).
The communication unit 2210 sends and receives signals as stated
above. Hence, the communication unit 2210 can be referred to as a
transmitter, a receiver, or a transceiver.
The storage unit 2220 stores a basic program for operations of the
device, an application program, and data such as setting
information. For example, the storage unit 2220 can store data
sharing history using the second RAT. For example, the history can
include a list of other devices sharing the data using the second
RAT. The storage unit 2220 provides the stored data according to a
request of the control unit 2230.
The control unit 2230 controls the operations of the device. For
example, the control unit 2230 sends and receives the signals
through the communication unit 2210. The control unit 2230 records
and reads data to and from the storage unit 2220. For doing so, the
control unit 2230 can include at least one processor. For example,
the control unit 2230 can include a Communication Processor (CP)
for controlling the communication or an Application Processor (AP)
for controlling a higher layer such as an application. The control
unit 2230 includes a link setter 2232 for controlling the link
setup based on the interoperation of different RATs using the first
module 2212 and the second module 2214. For example, the control
unit 2230 can control the device to serve as the control device 110
or one of the candidate devices 120 as described in FIG. 5 through
FIG. 21. The control unit 2230 operates as follows.
When the device serves as the control device, the control unit 2230
transmits information notifying a discovery interval start time for
the second RAT, through the first module 2212. The information
notifying the discovery interval start time is delivered by a first
RAT broadcasting signal, and the broadcasting signal can further
include personal identification information of the control device.
For example, the information notifying the discovery interval start
time includes at least one parameter indicating a remaining time
from the transmission of the information notifying the discovery
interval start time until the start time. The control unit 2230
transmits a discovery signal during the discovery interval through
the second module 2214. During the first interval of the discovery
interval, the control unit 2230 transmits TX-beamformed signals in
a plurality of directions through the second module 2214. During
the second interval of the discovery interval, the control unit
2230 transmits the discovery signal using an omni-directional beam
through the second module 2214. According to another embodiment of
the present disclosure, in the second interval, the control unit
2230 can detect signals TX-beamformed by the candidate devices,
without sending the discovery signals. In this case, the control
unit 2230 can distribute slots of the second interval to the
candidate devices before the first interval, send the slot
allocation result through the first module 221, and receive signals
from corresponding candidate devices in the slots. Further, the
control unit 2230 can send feedback notifying the detection result
to the corresponding candidate device in each slot.
When the device serves as the control device, the control unit 2230
can transmit the information indicating the discovery interval
start time and then receive an ACK from at least one candidate
device. In this case, when receiving ACKs from all of the candidate
devices, the control unit 2230 can suspend the transmission of the
information indicating the discovery interval start time. For doing
so, the control unit 2230 can determine the candidate devices prior
to the operation 2001. For example, the control unit 2230 can
determine the candidate devices by conducting the discovery process
using the first RAT or identifying data sharing devices using the
second RAT.
When the device serves as the control device, the control unit 2230
can send a signal notifying a list of at least one candidate device
for data sharing. In this case, some devices not included in the
list among the candidate devices can avoid unnecessary power
consumption by disabling the communication module for the second
RAT.
When the device serves as the candidate device, the control unit
2230 receives information indicating a discovery interval start
time for the second RAT, through the first module 2212. The control
unit 2230 receives a discovery signal during the discovery interval
through the second module 2214. During the first interval of the
discovery interval, the control unit 2230 detects one of
TX-beamformed signals from the control device in a plurality of
directions. During the second interval of the discovery interval,
the control unit 2230 detects at least one of discovery signals
from the control device over an omni-directional beam. According to
another embodiment of the present disclosure, during the second
interval, the control unit 2230 can control to send the discovery
signals TX-beamformed in different directions in its allocated
slot, without detecting the discovery signals. In this case, the
control unit 2230 can receive the slot allocation result of the
second interval from the control device, and receive from the
control device feedback notifying the detection result of the
signals transmitted to the candidate device.
When the device serves as the candidate device, the control unit
2230 can receive information indicating the discovery interval
start time and then send an ACK to the control device. The ACK can
include identification information of the candidate device.
When the device serves as the candidate device, the control unit
2230 can fail in the discovery signal detection. In this case, the
control unit 2230 can receive a signal notifying a list of at least
one candidate device for data sharing, from the control device
through the first module 2212. When the candidate device is not
included in the list, the control unit 2230 can disable the second
module 2214 and thus avoid unnecessary power consumption.
The control unit 2230 can control to display at least one item
indicating at least one neighboring device discovered. For doing
so, although not depicted in FIG. 22, the electronic device can
further include a UI module for outputting information and
detecting a user's input under the control of the control unit
2230. The UI module can include at least one hardware module for
the outputting and the inputting. For example, the hardware module
can include at least one of a sensor, a keyboard, a keypad, a
speaker, a microphone, a touch screen, a Liquid Crystal Display
(LCD), a Light Emitting Diode (LED), a Light emitting Polymer
Display (LPD), an Organic Light Emitting Diode (OLED), an Active
Matrix Organic Light Emitting Diode (AMOLED), and a Flexible LED
(FLED). Since the UI module can include a display means, it can be
referred to as a display unit.
When the control device and the candidate devices can communicate
with each other using the second RAT, a distance and an angle
between the devices can be further estimated. The distance and the
angle can be used for the user to select a device for sharing
contents or a service from the candidate devices. UI/UX for the
content or service sharing can be configured as follows.
FIGS. 23A and 23B depict an interface for content sharing using
link setup according to an embodiment of the present disclosure.
That is, the link setup is utilized. FIGS. 23A and 23B show a UI/UX
for the data sharing provided from the control device 110 to the
user.
Referring to FIG. 23A, the control device 110 executes an
application which displays image contents. Hence, the control
device 110 displays a list of images and a selected image. To share
the selected image, the user applies a predefined touch input to a
point 2382 on a region displaying the selected image. The
predefined touch input is to share data and can be defined as a
long press. The long press is a touch input pressing one point over
a certain time. For example, the certain time can be defined as one
or two seconds. The control device 110 detects a content sharing
command.
Referring to FIG. 23B, the control device 110 displays other
devices for data sharing. More specifically, the control device 110
displays a UI 2384 showing other sharing devices in an image
displaying region. The UI 2384 can be referred to as a neighboring
device map. The UI 2384 includes a thumbnail or a reduced image of
the selected image, and includes items notifying the other sharing
devices. According to another embodiment of the present disclosure,
the thumbnail or the reduced image can be omitted. That is, upon
detecting the content sharing command, the control device 110 can
perform the present link setup. That is, the control device 110
carries out the method of FIG. 3 using the first RAT and the second
RAT, identifies devices for the link setup using the second RAT,
and then displays the link setup devices on the UI 2384.
With the UI/UX of FIGS. 23A and 23B, the user can effectively
achieve instantaneous data sharing during content browsing.
Further, the link setup allows the data sharing during a short
time.
FIG. 24 is a flowchart of a content sharing method using link setup
according to an embodiment of the present disclosure. FIG. 24
illustrates operations of the control device 110 for providing the
interface of FIGS. 23A and 23B.
Referring to FIG. 24, the control device 110 determines whether a
content sharing command occurs in operation 2401. The control
device 110 is displaying contents (e.g., photos, videos, etc.).
Upon detecting a predefined user input, the control device 110 can
recognize the content sharing command. For example, the predefined
user input can be defined as a long press at a fixed point over a
certain time.
When detecting the sharing command, the control device 110 performs
the discovery in operation 2403. That is, the control device 110
executes the method of FIG. 3 using the first RAT and the second
RAT. More specifically, the control device 110 can send information
notifying a discovery interval start time for the second RAT, using
the first RAT, and then send a discovery signal using the second
RAT during the discovery interval. Further, the control device 110
can estimate an angle and a distance of at least one neighboring
device discovered.
In operation 2405, the control device 110 displays a content
thumbnail and at least one item indicating the at least one
neighboring device. Herein, the at least one item is displayed
according to the angle. Specifically, the at least one item is
displayed at a location corresponding to the angle based on the
thumbnail. The item can indicate a type of the corresponding
neighboring device or owner's identification information. For
example, the thumbnail and the at least one item can be displayed
as shown in FIG. 23B.
The interface of FIG. 23B represents a location of at least one
neighboring device on a two-dimensional plane. However, a real
space is three-dimensional and a location includes a height. Since
the two-dimensional representation of FIGS. 23A and 23B cannot
distinguish the height, it is hard for the user to select a
connection device. To address such a difficulty, the device can
provide an interface of FIGS. 25A through 25D according to another
embodiment of the present disclosure.
FIGS. 25A through 25D depict interfaces displaying neighboring
devices in an electronic device according to an embodiment of the
present disclosure. That is, FIGS. 25A through 25D depict another
application of the present link setup. In FIGS. 25A through 25D,
the control device 110 provides a UI/UX for data sharing to the
user.
Referring to FIG. 25A, neighboring devices 2520-1, 2520-2, and
2520-3 are positioned at the same coordinates on an x-y plane and
at different coordinates on a z-axis. That is, the locations of the
neighboring devices 2520-1, 2520-2, and 2520-3 are distinguished
based on the height in FIG. 25A. The device can discover the
neighboring devices 2520-1, 2520-2, and 2520-3, and then display
the neighboring devices 2520-1, 2520-2, and 2520-3 using the
interface of FIG. 25B, 25C, or 25D. In FIGS. 25B, 25C, and 25D,
items of the neighboring devices 2520-1, 2520-2, and 2520-3 are
configured in similar shapes to the neighboring devices 2520-1,
2520-2, and 2520-3. According to another embodiment of the present
disclosure, items can employ different shapes and colors.
Referring to FIG. 25B, the device represents a three-dimensional
space and displays the neighboring devices 2520-1, 2520-2, and
2520-3 in the three-dimensional space. The device can further
display other neighboring devices. To enhance visibility of the
three-dimensional space, the device can also display a guide line
as expressed as dotted lines in FIG. 25B. According to another
embodiment of the present disclosure, the guide line can be
omitted.
Referring to FIG. 25C, the device displays a two-dimensional map.
Yet, when other devices with different heights overlap at the same
location on the two-dimensional plane, the device groups the other
devices and then displays them vertically. That is, the device
groups and displays the neighboring devices 2520-1, 2520-2, and
2520-3 vertically. The grouping can be represented as a polygon as
expressed as an alternated long and short dash line of FIG. 25C,
and the height of the neighboring devices 2520-1, 2520-2, and
2520-3 can be represented using breadth changes of the polygon.
Alternatively or additionally, the device can represent the height
by displaying the lower device item smaller than the higher
device.
Referring to FIG. 25D, the device displays a two-dimensional map.
Unlike FIGS. 23A and 23B, the device displays a y-z plane, rather
than the x-y plane. Hence, the neighboring devices 2520-1, 2520-2,
and 2520-3 of the different heights are distinguished vertically on
a screen. That is, the representation is based on top, bottom,
left, and right, rather than front, back, left, and right.
The above-described methods according to claims or various
embodiments of the present disclosure can be implemented in
software, firmware, hardware, or in their combinations.
As for the software, a computer-readable storage medium storing one
or more programs (software modules) can be provided. One or more
programs stored in the computer-readable storage medium can be
configured for execution by one or more processors of the
electronic device. One or more programs can include instructions
for controlling the electronic device to execute the methods
according to the exemplary embodiments of the present
disclosure.
Such a program (software module, software) can be stored to a
random access memory, a non-volatile memory including a flash
memory, a Read Only Memory (ROM), an Electrically Erasable
Programmable ROM (EEPROM), a magnetic disc storage device, a
Compact Disc (CD)-ROM, Digital Versatile Discs (DVDs) or other
optical storage devices, and a magnetic cassette. Alternatively,
the programs can be stored to a memory combining part or all of
those recording media. A plurality of memories may be equipped.
The programs can be stored in an attachable storage device
accessible via a communication network such as Internet, Intranet,
Local Area Network (LAN), WLAN, or Storage Area Network (SAN), or a
communication network by combining these networks. The storage
device can access the electronic device through an external port. A
separate storage device may access the electronic device over the
communication network.
As set forth above, the link setup can be accomplished more
efficiently by synchronizing the discovery interval using different
RATs in the wireless communication system.
Although the present disclosure has been described with an
exemplary embodiment, various changes and modifications may be
suggested to one skilled in the art. It is intended that the
present disclosure encompass such changes and modifications as fall
within the scope of the appended claims.
* * * * *